具有LList打印输出的树/哈希图

Question

My program takes in an text file and stores every unique word (or grouping of characters) as the key in a map and also stores a linked list of the line numbers that each word appears on. I also implemented an occurance counter in the printEntry method.

My problem is that I am trying to avoid printing the same line number twice if a single word appears more than once on a line. I have fooled around with the if statement in the printEntry method and seem to be getting close, but still no cigar. I do NOT want to block the duplicate line number from being added to the list because it still needs to be counted to increment the occurance variable.

Here is an input that would cause me trouble:

keyboard
mouse mouse
mouse

I need the output to look like this:

ID: keyboard  Line Numbers: 1  Occurance: 1
ID: mouse  Line Numbers: 2,3  Occurance 3

I will only provide the printEntry method for now to keep the post short. If needed, I can provide further code. Thanks.

public static void printEntry(Map.Entry entry){

    //local occurance variable
    int occurance = 1;

    //print the word and the line numbers as well as test for duplicate line integers on the same key
    Iterator itr = ((LinkedList) entry.getValue()).iterator();
    System.out.print("ID: " + entry.getKey() + "   Lines: " + itr.next());

    //object variable to store previous line number
    Object check = itr.next();
    while(itr.hasNext()){
        occurance++;
        if (check != itr.next()){
            System.out.print(", " + itr.next());
        }
        else {
            System.out.println("Skipped duplicate");
        }
    }
    //prints occurance from incremented occurance variable
    System.out.print("  " + " Occurance: " + occurance);
    System.out.println();
}

Edit-

I would like all of an entry's information to appear all on the same line as we are going to be scanning large(r) documents. I have formatted the printEntry method close to where I would like it, but cannot figure out how to do it with the for loop.

        public void printEntry(Map.Entry<String, WordStats> entry) {
    String word = entry.getKey();
    WordStats stats = entry.getValue();

    System.out.print("ID: " + word + "  Occurrences: " 
                       + stats.getOccurrences() + " Lines: ");
    for (Integer lineNumber : stats.getLines()) {
        System.out.println(lineNumber);
    }
}

Answer 1

So you want, for each word, to keep

• the number of times it appears
• a sorted set of line numbers where it appears (and by set, I mean no duplicate line numbers)

So just do that:

public class WordStats {
    private int occurrences;
    private SortedSet<Integer> lineNumbers = new TreeSet<Integer>();

    public void addOccurrence(int lineNumber) {
        occurrences++; 
        lineNumbers.add(lineNumber);
    }

    // getters ommitted for brevity
}

And now just use a Map<String, WordStats> . For each word in the text, add a WordStats if it isn't in the map yet, and add an occurrence to its WordStats instance.

The printEntry method would then look like:

public void printEntry(Map.Entry<String, WordStats> entry) {
    String word = entry.getKey();
    WordStats stats = entry.getValue();
    System.out.println("The word " + word + " has been met " 
                       + stats.getOccurrences() + " time(s), on the following line(s):");
    for (Integer lineNumber : stats.getLines()) {
        System.out.println(lineNumber);
    }
}